Preparation of covalently bonded silica-alginate hybrid hydrogels by SCHIFF base and sol-gel reactions

Organic-inorganic hybrid materials overcome drawbacks associated with alginate hydrogels. In this work, covalently coupled silica-alginate hybrids were prepared by Schiff base formation and sol-gel reaction using dialdehyde (ADA), (3-Aminopropyl) triethoxysilane (APTES), APTES/tetraethylorthosilicate (TEOS) precursors. The influence of the polysaccharide/inorganic ratio, nature inorganic precursor ionic crosslinking ability are studied. Prepared characterized FT-IR, 13 C 29 Si NMR spectroscopies, SEM, rheology. For ADA/APTES hybrids, at higher ADA content, is predominant, but lower prevalent. However, progress reactions for ADA/(APTES+TEOS), favored compositions. Introducing a posterior treatment was possible, increasing moduli in ADA/(APTES+TEOS) from 86,207 Pa 1.5 ADA/Si to 362,171 ADA/Si-Ca. In-situ ADA-Silica hydrogels containing both covalent can be successfully synthesized proposed method. CARBPOL-D-21-01042. • Alginate chemical oxidation allows synthesis class II. Synthesis includes competition reactions. Hybrids properties designed modifying proportion component. Ionic post-crosslinking enabled.